D-Day it attacked lines of communication and fortifications on the coast. It was part of the aerial barrage during the opening stage of Operation Cobra, the breakout at Saint Lo. In late August 1944, the squadron left England for Lessay Airfield, an advanced landing ground in France. From the continent, it began flying night missions, with its first night mission against batteries near Saint-Malo. It also carried out night missions against ammunition dumps and fuel storage areas. In September, it attacked fortifications near Brest, France, and as allied forces advanced across France, toward the Siegfried Line shifted its operations primarily to targets in eastern France. The squadron was awarded a Distinguished Unit Citation for striking transportation hubs used by the Wehrmacht to bring reinforcements to the Ardennes during the Battle of the Bulge. The 456th flew interdiction missions in the Ruhr as the Allies drove across Germany and attacked enemy communications. It flew its last combat in April 1945, then moved to Kempten, Germany, where it participated in the program to disarm Germany. It returned to the United States in November and was inactivated at Camp Myles Standish, Massachusetts, the port of embarkation, a day later. Air Force Reserve The squadron was reactivated under Air Defense Command (ADC) as a reserve unit at Tinker Field in September 1947. At Tinker, it trained under the supervision of ADC's 177th AAF Base Unit (Reserve Training), later the 2592d Air Force Reserve Training Center. It is not clear whether or not the squadron was fully staffed or equipped prior to 1949. The squadron flew a mix of trainers and Douglas A-26 Invaders. In 1948 Continental Air Command (ConAC) assumed responsibility for managing reserve and Air National Guard units from ADC. ConAC reorganized its reserve units under the wing base organization system in June 1949. The new wings were manned at only 25% of their normal strength. All reserve combat units were mobilized for the Korean war. The squadron was mobilized on 10 March 1951. Its personnel and aircraft were used as fillers for other organizations and the squadron was inactivated a week later. Strategic Air Command The 656th Bombardment Squadron, the second predecessor of the 556th, was activated as part of the 68th Bombardment Wing at Lake Charles Air Force Base, Louisiana in 1953, when it assumed the personnel and equipment of the 24th Bombardment Squadron, which was simultaneously inactivated. The squadron took